Salt of beta-propiolactone adduct of rosin and sizing compositions made therefrom



United States Patent 3,423,220 SALT OF ,B-PROPIOLACTONE ADDUCT OF ROSIN AND SIZING COMPOSITIONS MADE THEREFROM Carl Bordenca, Ponte Vedra Beach, Fla., assignor, by mesne assignments, to SCM Corporation, New York, N.Y., a corporation of New York No Drawing. Filed Aug. 10, 1966, Ser. No. 571,391 US. Cl. 106238 Claims Int. Cl. D21h 3/34 ABSTRACT OF THE DISCLOSURE Novel salts of ,B-propiolactone adduct of the acids of tall oil, gum, and wood rosins, sizing compositions made therefrom, and processes for sizing a cellulosic web are described. The novel salts, sizing compositions, and processes are advantageous in that they permit the sizing of a cellulosic web with improved efiiciency and the suppression of crystal formation which is undesirable in sizes.

This invention relates to a composition of matter that is useful as sizing for a cellulosic web. More particularly, the invention relates to certain salts of the fi-propiolactone adduct of resin acids.

By resin acids is meant those acids which make up the preponderance of tall oil rosin, gum rosin, and wood rosin, these rosins serving as such are a suitable starting material for making the adduct. The resin acids include abietic, levopimaric, neoabietic, dehydroabietic, dihydroabietic, tetrahydroabietic, pimaric, isopimaric, and painstric acids. The conjugated ones of these are abietic, levopimaric, neoabietic, and palustric acids.

An advantage of the compositions of this invention over prior proposals includes their ability to size a cellulosic membrane such as paper with improved efficiency. A further advantage, when using tall oil rosin particularly, is that of suppressing crystal formation, which is undesirable in size compositions.

The inventive salts here are the water dispersible alkali metal (including lithium) salts, ammonium salts, and substituted ammonium salts of the beta propiolactone adduct of resin acids and mixtures thereof. The sizing compositions of the invention are these salts dispersed in aqueous medium, usually in concentration of about /2 to about 5 weight percent for facility of use. The instant process of sizing comprises applying such dispersion onto the web or into the furnish from which the web is formed. The size is set onto the cellulosic fibers conventionally, e.g. with papermakers alum.

The adduct can be made in accordance with method of Halbrook et 211., Industrial and Engineering Chemistry, volume 2, No. 3, September 1963, for adding fl-propiolactone to levopimaric acid. Suitably, if desired for control of color, etc., the crude adduct can be purified for salt formation by dissolving it in benzene or other aromatic hydrocarbon solvent, then precipitating the adduct by dilution of the resulting solution with an aliphatic hydrocarbon such as heptane, an aliphatic petroleum naphtha boiling in the range from 50 to 400 F., or the like (preferably for efiiciency and economy one that is readily stripped off by distillation at atmospheric pressure) followed by chilling and filtration.

To make the salt the adduct is pulverized for efficient reaction, suitably by cold grinding, and mixed with an aqueous solution of the base, e.g. sodium hydroxide, sodium carbonate, sodium bicarbonate, ammonium hydroxide, amine solution, and the heat of neutralization removed. Suitable salt forming bases include the water soluble hydroxides, carbonates, and bicarbonates of the metals and ammonium, and also water soluble amines 3,423,220 Patented Jan. 21, 1969 such as ethanolamine, diisopropanol amine, ethylene diamine, monoethyl amine and the like.

By a water dispersible salt what is meant is one that can be stably dispersed at concentrations of at least 5% by weight solids (N.V.M.) in water at room temperature with mechanical mixing in the absence of emulsifying or other additives and remain stable in this form for at least 12 hours.

In using a whole rosin, such as tall oil rosin, as the source of resin acids to make the adduct one can heat the melted rosin with incremental porportions of the lactone at a temperature between about 175 and 225 C., employing in all between about 2 and about 40 weight parts of lactone per parts of rosin. Low boiling byproducts and excess lactone, etc., distill from the mass. While not intending to be bound by theory, the adduct formation presently postulated appears to take place from the lactone adding to conjugated resin acids. Accordingly, it is preferred for eificiency and economy to use only suflicient lactone to adduct with the conjugated resin acids estimated to be present, generally thus about l5-25 weight parts of lactone per 100 parts of rosin charged to the reactor.

Having thus described the invention generally, the following is presented in illustration but not in limitation of the invention:

Example 1 1500 grams of tall oil rosin, Acid No. 167, were charged to a 3-liter resin kettle and melted under nitrogen. The temperature was held at 180 C. 330 grams of the lactone were then added over 1 /2 hours. The temperature rose to 212 C. and then fell to 180 C. The re action mixture was refluxed with stirring four hours at 180 C. At this point 15 ml. of a low boiler, boiling point about C., was distilled off. The kettle temperature then rose to 215 C. where it was held for two hours and the product poured off. The resulting crude adduct had an acid value of 240.

The adduct was then purified by crushing and dissolv ing 1628 grams thereof in 1855 ml. of benzene with warming on a waterbath. 8150 ml. of heptane were then added. The batch stood overnight and was then chilled to 26 C. 'before filtration. The heptane was distilled off from the precipitate until the temperature reached C. At this point there was recovered 980 grams of purified adduct. The acid value of the purified adduct was 246, this indicating that the proportion of lactone combining was substantially equimolar with the conjugated resin acids of the rosin used.

This sodium salt of the adduct was made as follows:

500 grams of the purified adduct were ground with Dry Ice. The resulting powder was then added rapidly to a vigorously stirred solution containing 89 grams of sodium hydroxide and 236 grams of water. Vigorous agitation was continued for five minutes, during which time the mixture became hot and was allowed to cool. The resulting product had the appearance and color of petrolatum and was useful as a paste size, and could be diluted further with water to form a dispersion stable at room temperature.

Example 2 The paste size of the preceding example was compared with conventionel fortified and unfortified rosin paper sizes on bleached kraft paper pulp by the Cobb size test. The sizes were diluted with water to 10% solids content by weight and added to the paper pulp in the weight percentages indicated, basis weight of dry fiber in the pulp. The sizes were set with papermakers alum, sheets were formed, couched off on to blotters, wet pressed between felts, and dried. The basic weight of the sheets were 40 lbs. per ream (24 x 36 x 500). The table below summarizes the test results on this stock at various percentages of size.

TABLE X.COBB SIZE TEST Wet pick-up (av. of two tests),

g./sq. In.

* Some penetration of water through sample during test.

A size similar to that of Example 1 was made using ammonium hydroxide. It performed in about the same way as the size of Example 1.

What is claimed is:

1. The water dispersible salt of the fi-propiolactone adduct of resin acids selected from the group consisting of abietic, levopimaric, neoabietic, dehydroabietic, dihydroabietic, tetrahydroabietic, pimaric, isopimaric, and palustric acids and mixtures thereof, said salt being selected from the group consisting of alkali metal, ammonium, and salt-forming water soluble amines of said adduct.

2. The sodium salt according to claim 1.

3. The ammonium salt according to claim 1.

4. The salt of claim 1 wherein said resin acids comprise at least one conjugated resin acid.

5. A sizing composition for a cellulosic web comprising an aqueous dispersion of from about /2 to about 5 weight percent, basis, the weight of the dispersion, of a water dispersible salt of the ,B-propiolactone adduct of resin acids selected from the group consisting of abietic, levopimaric, neoabietic, dehydroabietic, dihydroabietic, tetrahydroabietic, pimaric, isopimaric, and palustric acids and mixtures thereof, said salt being selected from the group consisting of alkali metal, ammonium, and saltforming water soluble amines of said adduct.

6. The sizing composition of claim 5 wherein said salt is sodium.

7. The sizing composition of claim 5 wherein said salt is ammonium.

8. The sizing composition of claim 5 wherein said resin acids are supplied by use of a straight rosin.

9. The sizing composition of claim 5 wherein said straight rosin is tall oil rosin.

10. The process for sizing a cellulosic web which comprises applying the composition of claim 5 to cellulosic fibers prior to or after they are formed into said web.

References Cited UNITED STATES PATENTS 2,994,635 8/1961 Reaville et al. 260-97.5 3,030,221 4/1962 Watkins 106--238 3,044,890 7/1962 Boughton et al. 106238 3,291,785 12/1966 Halbrook et al. 26097 ALLAN LIEBERMAN, Primary Examiner.

US. Cl. X.R. 

